The plan, city officials have said, is a response to complaints from residents and business owners about loud music, public drunkenness and boisterous behavior during the weekend when throngs of visitors descend upon the city from all over the country.

Miami Beach will impose street closures, video surveillance and increased police presence — two officers on every corner — as well as a DUI checkpoint on the MacArthur Causeway. License plate scanners are being installed to record vehicle tags of cars entering the beach via the Julia Tuttle and MacArthur causeways. The tags, which will be entered into a database, will reveal outstanding warrants and other vehicle violations that police can use to stop drivers.

The city's harder stance on security also is in response to last year's weekend when 11 officers shot and killed Raymond Herisse in a hail of more than 100 bullets. The incident took place about 4 a.m. on Collins Avenue near the Loews Hotel. According to police and witness reports, Herisse of Boynton Beach did not stop when officers asked him to. When Herisse sped off, officers responded with fire. Four bystanders were wounded. The shooting remains under investigation.

The new measures are not going down well in some quarters.

“We are this year very, very concerned that Miami Beach has set a course that is overly aggressive. It sends a strong message to African Americans that they are not welcome in the city,” said Jeanne Baker, chairwoman of the Police Practices Committee of the Miami chapter of the American Civil Liberties Union.

The ACLU, which has monitored police conduct since the festival started, will send trained legal observers to the beach to record and report police actions that might be considered excessive, Baker said.

Recalling an occasion where she intervened, Baker said police had set up a checkpoint on Collins Avenue and were directing vehicles into an alleyway. “Drivers were being asked to step out and were being interrogated by police,” Baker said.

Police were citing vehicle violations — from loud music to tinted windows.

“They were not responding to any threatened breaches of public safety or anything that was crying out for police attention,” Baker said. “My complaint was that this is a big show of police force without cause.”

Baker reported the incident to police officials, who ended the checkpoint.

Other organizations, including the Miami Dade Branch of the NAACP, are collaborating with the ACLU in sending members to help monitor the police, said Bradford Brown, NAACP branch first vice president.

The NAACP has met with the ACLU and the U.S. Department of Justice, which will also monitor police behavior, and with the Miami-Dade Community Relations Board, which will send hundreds of county employees to serve as “goodwill ambassadors,” Brown said.

One goal of the goodwill ambassadors is to make festival-goers aware of the rules, said CRB chairman the Rev. Dr. Walter T. Richardson.

“Their job is to help warn citizens and visitors and guests of borderline activities that could bring about police action,” said Richardson, who has served as a goodwill ambassador and as a member of the God Squad, a group of South Florida ministers who come out to advise visitors.

“I saw a young man who was drinking while he was walking. I told him it was against the law,” Richardson said.

Amy Carswell, director of the CRB, which comes under the county’s Office of Community Advocacy, said she anticipates as many

as 200 county employees will serve as goodwill ambassadors this year. For every hour they work, volunteers will get one-half hour compensation time, she said.

“Sometimes, in the past, we had concerns that clubs were overbooking, which led to confrontations,” Carswell said. “The ambassadors try to encourage visitors to follow the law and (they try to) be intermediaries between visitors and residents, visitors and business owners, visitors and police.”

Carswell said the city’s plan is a good idea.

“The strategies that the city is implementing are to keep things peaceful: Get people to park; keep people from speeding through the neighborhoods. It all sounds good. The problem from the city’s perspective is that only so many people can fit into this small area. The effort is to control the numbers of people who come in so that it becomes manageable for everybody.”

But Adora Obi Nweze, president of the NAACP’s Florida State Conference, disagrees.

“You control animals, not human beings,” Nweze said. “I am certainly reminded of when Miami Beach had a sign at all of its entrances: ‘No Niggers, no Jews, no dogs.’ There is no difference here now.”

“It’s unfortunate that we do it at a cost of being disrespected,“ Nweze said. “This is a situation that we in Miami, in my opinion, need to express ourselves about how we feel about them doing this to people of color. Maybe people of color ought to get the whole message that we really are not welcomed here.”

IF YOU GO Visitors for the Urban Weekend celebration will begin pouring into Miami Beach this Thursday and the festival will be under way until Monday. Ocean Drive will be closed to traffic. Collins Avenue traffic will be one-way going north and Washington Avenue will be one-way going south.

Miami Heat players Dwyane Wade and Udonis Haslem have endorsed Miami Beach’s “Respect the Scene” outreach campaign which encourages visitors to “stash your trash,’’ keep alcoholic drinks inside and to keep noise to a minimum. To see the promotion, go to respectthescene.com.

Miami-Dade County’s “Goodwill Ambassadors” will be available to advise visitors. ACLU volunteers will be on hand to monitor police activity.

The NAACP will field phone calls and email from festival participants who encounter problems. Call 305-685-8694 or email ethel.duncan@naacpmiamidade.org